45-70 at 900 meters

[guninhand]

This summer I'll be shooting 45-70 at a 900 meter bpcr match for the first time. I've read some say you need 1250 fps at the muzzle to score at that distance. At present I'm used to 1175fps muzzle speed with a standard deviation of 12.6fps. When I put the data into a trajectory calculator I get a 900 meter speed of 744fps for the 1175fps launch and 761fps for the 1250fps launch. The bullet is a 505 grain Creedmore style.

My question is; is this 1250 fps at muzzle/761fps at 900 meters an accepted minimum, or is there some other value? I have access to a 900 meter range to practice/experiment.

If I have to jack up the propellant to unpleasant recoil levels then I will have a dedicated load for the extreme distances, 900 meters and maybe 800 meters, and the old standby for shorter distances.

[RMulhern]

What loading are you using?

[Lead pot]

The load your using will do just fine at 800.
I used a 485 grain FN @ about your load at 1175fps and had no problem staying on target at 807 yards.

[Don McDowell]

Some places have a minimum velocity requirement for pit safety. You'll need to check that out.
Having said that I've had pretty decent results in gong matches at 1000 yds with my 45-70 using loads that range from 1150-1200 fps with bullets from the 500-530 gr range.
So unless your most accurate load doesn't meet the range requirements, go for it. Let us know how you did.

[guninhand]

Thanks for the replies. Looks like I'll just work out with the standard load and adjust if it dies at 900. The standard load is 44 grains of 777ffg. For various reasons it's my only viable option. I've almost perfected a load of about 20 grains of 2400 and filler to mimic it as a cheap practice load. Around 27 grains of IMR 4198 might work as well. After tweaking I'll use the one with least standard deviation.

[John Boy]

GIH, here are some of under 1250 fps that I've shot @ 1000yds with no complaints

HiWall (237 MOA)
45-70 Lyman 457125 505 0.391 1:40 Starline Fed 150 Goex Ctg 69 0.060 Felt 2.840COL 1118 fps

74 Sharps (169MOA) - HiWall (225MOA) & H&R Buffalo Classic (169MOA)
45-70 Lyman Postell 522 361 1:20 Starline Br2 Cartridge 70gr .02 Felt 1126 fps

74 Sharps & Highwall for both
45-70 PJ Creedmoor 538 0.365 1:20 Starline Fed 150 CTG-Sifted 70 0..03 Dry Felt 3.250 1103fps
45-70 PJ Creedmoor 538 0.365 1:20 Starline Fed 155 CTG-Sifted 70 0..03 Dry Felt 3.250 1098fps

If you use Swiss 1.5 or FFg or Goex FFFg you'll be in the 1200+ fps velocities

[waksupi]

I always liked keeping mine just sub-sonic.

[guninhand]

Thanks JB, That is encouraging data. I'm using straight wheelweights ( fluxed to the nth degree) and .03 LDPE, BC 0.382. It would be nice to deal with only one load.

[Don McDowell]

If you're not going to use blackpowder, then keep things simple and go with 25 grs of 5744. You won't have to worry about it eating your cases like the substuff does, and it will shoot a lot more accurately.

[ss40_70]

a friend shot this target using barrel sights at 100 yds .. 45/70 with 25 1/2 grains aa5744 and a 500 grain r/n lee boolit ... and there is 5 shots threw the hole .. http://i845.photobucket.com/albums/ab11/stephen4570/IMG_0003.jpg

[bigted]

well now id say thats a very nice group...well done!

[hydraulic]

I've managed to get on the target ( full sized buffalo gong) at 915 yards using 72 grs. of Swiss 1 1/2 with .250 compression under the RCBS 535 gr. bullet with Emmets lube. Seems the wind always blows from a different direction what ever day I get up to our South Dakota range, and when it comes from the SE you can't hear your hits. The Mrs. is getting pretty good on the scope, however. I have 184 minutes on my MVA sights.